About the only good comparison we could do, is that of efficency in locomotion. Obviously thousands of beating cilia are more efficent than say one flagellum, some flagellates have two flagella but one is usually trailing and the other employed for locomotion. While as for a pseudopodium, putting one foot forward and dragging the rest along really doesn't get you anywhere quickly. Ciliates are the fastest and most difficult of the protozoa to follow in observation without adding some sort of medium to thicken the water or medium that they are in. Usually a small amount of a cellulose based paste will slow them down enough to get a really good look at them.

A word of note or trivia, on average the plasmodium of the myxomycete moves at about one inch per hour using its pseudopdia.

BTW another comparison to paramecium and the amoeba is that of feeding. The paramecium uses its cilia to draw in or collect food in the oral groove to ingest into the gullet, where as the amoeba uses its pseudopodia to surround and engulf (phagocytosis) its food. There maybe a number of other comparisons to be made if one would think about it.

Ken Ramos, Aviation Ordnanceman USN Ret.
Western North Carolina
"If you see an explosives handler running...try to keep up with him!"
Ken's Nature Study

Since flagella will guide the organism as it moves ... but Paramecium is lined with cilia, so does the Paramecium rotate at all as it moves?

Same question goes with Amoeba ... does it rotate at all? or does it simply extend its pseudopod in the direction that it needs to go, so it's not really 'rotation' in the traditional sense [I do hope this make sense!]

Yes there is rotation in the paramecium as it swims along, due to the beat of the cilia which covers its body or covers the cell, maybe I should say. At any case it does rotate as it swims. The amoeba on the other hand, flows slowly along its path. However you may find this interesting in the amoeba Chaos carolinense, it will sometimes "walk" on the substratum that it may be on! This is accomplished by raising itself upon its pseudopodia and then extending one forward after another. These are quite large for ameobae since there size can reach anywhere from 1-5mm, makeing them visible to the naked eye and amazing to observe through the microscope.

Ken Ramos, Aviation Ordnanceman USN Ret.
Western North Carolina
"If you see an explosives handler running...try to keep up with him!"
Ken's Nature Study

Ken Ramos wrote:About the only good comparison we could do, is that of efficency in locomotion. Obviously thousands of beating cilia are more efficent than say one flagellum, some flagellates have two flagella but one is usually trailing and the other employed for locomotion.

I forgot to comment, you said that some organisms have two flagella, so that's like an Euglena, right?

I would feel more optimistic about a bright future for man if he spent less time proving that he can outwit nature and more time tasting her sweetness and respecting her seniority. ~ E. B. White

On average I would venture to say about one half the size of most, not all, amoebae. Most of the trypanosmes I have listed are in the range of 25 microns up to about 65 microns (um). As for the amoeba, some are as small as 4um ranging in size up to 600um, with the exception of Chaos carolinesis which can be from 1-5mm in size. Most of the amoeba normally encounted by myself now, are from 80um up to about 230um. That is where I am getting my size average in relation to the trypanosomes. Sizes of micro organisms are so varied by species, that to say one is relatively larger than the next or smaller than the next on average, would be in my opinion be difficult to say.

bionewbe also asked:

I forgot to comment, you said that some organisms have two flagella, so that's like an Euglena, right?

Well I do not know of any Euglena that have two flagellums but that is not to say that there are not any. Just that I do not know of any Euglena with two. Now there are other flagellated protozoans which do have two flagella but one is usually trailing and not employed in swimming as is the other.

Ken Ramos, Aviation Ordnanceman USN Ret.
Western North Carolina
"If you see an explosives handler running...try to keep up with him!"
Ken's Nature Study

Ken Ramos wrote:Well I do not know of any Euglena that have two flagellums but that is not to say that there are not any. Just that I do not know of any Euglena with two. Now there are other flagellated protozoans which do have two flagella but one is usually trailing and not employed in swimming as is the other.

I hope that I didn't confuse you when I mentioned Englenas - which I associate with Euglenids which is one of the flagellate groups. I'm just wonderng what kind of movements can be observed in Euglenas ...

I would feel more optimistic about a bright future for man if he spent less time proving that he can outwit nature and more time tasting her sweetness and respecting her seniority. ~ E. B. White

Their movements are about as fast as ciliates, the flagellum can be seen extended in front of the eulgena and the tip moving about somewhat like a small propeller or screw. The entire flagellum does not move, only the tip of it while swimming. When changing extreme directions the whole flagellum will bend but still only the tip is propelling or pulling the euglena through the water. Cilia on the otherhand are more like tiny oars.

At present I have no photographs of Euglena but I do have a couple flagellates to show you. The flagellum is marked by an arrow in both images and they are quite hard to see, so look closely. Both of these organisms can alter the shape of their bodies as they change directions or casually move about. This is especially noted in Distigma proteus

By the way I forgot to note that Distigma proteus has two flagella (the shorter one not shown in the photograph) and does use both for swimming. Usually one flagellum trails along but not in the case of this organism. Jahns book, "How to Know the Protozoa" states: "the longer flagellum moves with a complicated spiral wave, the shorter one with a full length latero-posterior stroke."

Ken Ramos, Aviation Ordnanceman USN Ret.
Western North Carolina
"If you see an explosives handler running...try to keep up with him!"
Ken's Nature Study

Ken Ramos wrote:Their movements are about as fast as ciliates, the flagellum can be seen extended in front of the euglena and the tip moving about somewhat like a small propeller or screw. The entire flagellum does not move, only the tip of it while swimming. When changing extreme directions the whole flagellum will bend but still only the tip is propelling or pulling the euglena through the water. Cilia on the otherhand are more like tiny oars.

So, would the movements of a flagellum be smooth or "jerky"? or will it different depending on the organism itself?

I would feel more optimistic about a bright future for man if he spent less time proving that he can outwit nature and more time tasting her sweetness and respecting her seniority. ~ E. B. White

So, would the movements of a flagellum be smooth or "jerky"? or will it different depending on the organism itself?

I will go as far as to say that in my observations of flagellates, it would depend on the organism itself. The Peranema for example moves in a smooth, steady path while swimming; whereas some smaller flagellates seem to jump around, such as Chilomonas paramecium (not to be conufused with the ciliate paramecium). C. paramecium is quite small, about 40um and has two flagella with numerous small chloroplasts and one water expelling vesicle (wev). They are usually found in putrid plant infusions.

Ken Ramos, Aviation Ordnanceman USN Ret.
Western North Carolina
"If you see an explosives handler running...try to keep up with him!"
Ken's Nature Study